Algimantas Juozapavicius, Vilnius University, Lithuania
Dalius Mazeika, Vilnius Gediminas Technical University, Lithuania

GRID TECHNOLOGIES, WHY THEY�RE IMPORTANT

A computational grid is an infrastructure of both hardware and software.  It provides dependable, consistent, pervasive and inexpensive access to high-end computational capabilities.  The concept of �the grid� was coined in the mid-1990s to describe a distributed computing infrastructure for advanced science and engineering.
Grid computing makes it possible to unite pools of servers, storage systems and networks into a single, larger system so that the power of multiple-system resources can be delivered to a single user point for a specific purpose.  Internet users see unified content on the Web.  Similarly, the user of a grid essentially sees a single, but very large virtual computer.
At its core, grid computing is based on an open set of standards and protocols such as the Open Grid Services Architecture (OGSA).  These enable communications across heterogeneous and geographically dispersed environments.
Grid computing is the next logical step in distributed networking.  Just as the Internet allows users to share ideas and files which lead to projects, grid computing lets us share the resources of disparate computer systems so that people can work on such projects.  Grid computing allows users and organisations to optimise computing and data resources, to pool them for large capacity workloads, to share them across networks, and to enable collaboration.  Grid resources can be used to handle computing-intensive issues such as high-energy physics, the material sciences, genome research, and pharmaceutical development.
Grid infrastructure projects have also been pursued in the Baltic States.  These include the BalticGrid (www.balticgrid.org), the LitGrid programme (www.litgrid.lt), and grid-related initiatives in Estonia and Latvia.

ORIGINS

In Lithuania, grid initiatives date back to October 2004, when representatives from a project called �Enabling Grids for E-sciencE�, or EEGE, visited Lithuania.  Their ideas were very influential in Lithuania�s academic society, and enthusiasts from Vilnius University, the Vilnius Gediminas Technical University, the Kaunas University of Technology, and the IT company BGM soon completed work on their own grid test bed.  It was based on Globus Toolkit middleware, and all of the clusters in the test bed had their own certification authority.  Jobs from one cluster could be submitted to another through the use of trusted validation certificates.
The LitGrid project was presented to the Lithuanian Academy of Science and the Lithuanian State Science and Studies Foundation early in 2005 as an example of a grid infrastructure initiative.  The foundation had offered support to the project for two years, and, as noted above, eight academic institutions and one business partner took part.
During the subsequent two years, the infrastructure of the LitGrid has been developed and made available to Lithuanian scientists.  There are some 80 users of various kinds � distinguished scientists, researchers, doctoral and master�s degree students, among others.  The system has been integrated into the EGEE European grid infrastructure (www.eu-egee.org), and there are also close links to the BalticGrid, or the Baltic grid infrastructure.  Successful use has been made of numerous applications related to the material sciences, astrophysics, computational fluid dynamics, and mathematic modelling.

GOALS

The LitGrid programme is a long-term programme (2007-2012). It is a government-financed process aimed at deploying, developing and supporting Lithuania�s grid computing, service and communications infrastructure for the purposes of research and education.  The grid is to be integrated into the emerging European and Baltic grid infrastructures, and knowledge about grid technologies and the use of grids in Lithuania is to be brought up to the level which exists in those EU member states which have a longer history of experience with such issues.  Furthermore, Lithuania is expected to do more work in defining grid technology policies and in setting standards in this process.
The LitGrid programme is working on grid-based, parallel and distributed algorithms and other high-performance computing procedures for various research applications that are of interest and importance to Lithuanian scientists.  Partners in this programme are Vilnius University (the co-ordinator), the Institute of Mathematics and Informatics, the Institute of Physics, Klaipeda University, the Kaunas Medical University Institute of Psychophysiology and Rehabilitation, the Kaunas University of Technology, Siauliai University, the Vilnius Gediminas Technical University, the Vilnius University Institute of Theoretical Physics and Astronomy, and Vytautas Magnus University.

INFRASTRUCTURE, RESOURCES

The infrastructure of the LitGrid is based on gLite middleware, which is the main operational tool in uniting and merging the computer clusters of project partners.  An important element in the infrastructure is the Certification Authority, which is overseen by the BalticGrid.  These activities are to be analysed and modified as time goes on, always keeping in mind the needs of Lithuanian scientists.  There will also be efforts to become more active in relations with the EUGridMPA.  More than 600 CPU and 4 Tb of storage capacity are available for LitGrid users at this time.
LitGrid resources are monitored through an EGEE GOCdb monitor and a BalticGrid SAM test monitor.  Information for users is found at www.litgrid.lt, as are tutorials and user guides.

COLLABORATION WITH OTHER GRIDS

The LitGrid programme is in close collaboration with other European grid projects, particularly the BalticGrid and the EGEE.  The BalticGrid project has brought together key institutions from all three Baltic States to deploy a grid infrastructure in the Baltic region and to support national grid initiatives (NGI) in the region.  The BalticGrid infrastructure is used for applications related to biology, medicine, materials engineering and high-energy physics.  This is in line with the LitGrid goals, and the two projects are working very closely together.  The same goes for the European EGEE project.  The establishment of operational components and infrastructure, along with the design and development of certain components and procedures, pre-production testing, and other elements have been developed in close co-operation.

THE NETWORKING INFRASTRUCTURE

The LitGrid networking infrastructure is based on the Lithuanian Academic and Research Network (Litnet), and it brings together the computing and storage resources of all of its partners.  Throughput in the network is 100 Mb/s.  In the very near future, throughput is to be increased to 1 Gb/s.

GRIDCOM: A COLLABORATION TOOL

Gridcom (grid commander) is a user-friendly Web interface which allows users to launch applications on the grid.  It was developed at Vilnius University, and it provides a suitable platform and set of tools which enable co-operation among users and applications.  Gridcom provides an international and interdisciplinary forum for the exchange of ideas, bringing together people to find solutions in various areas of research.
The functionality of Gridcom includes a joint application repository for user groups (launching applications from the group), a joint file repository for users groups, joint forum and mailing capabilities, and a joint interface for visualisation and other application tools.
Gridcom also enables joint editing capabilities for files that are anchored to an application � various script files, application sharing, file sharing, etc.  The LitGrid and BalticGrid projects show how necessary such tools are if there is to be close collaboration among grid users.  Groups of users can keep their applications and input, output or other files as close together as possible so that they can be manipulated by all group participants.  Gridcom makes it possible to launch and run applications via mobile equipment, as well.

Author�s contacts: algimantas.juozapavicius(at)mif.vu.lt, +370-5219-3053